Vasopressin is a peptide hormone secreted by the posterior pituitary gland. Vasopressin is further described p. 1-3 in the International Patent Application WO 02/00626 with the international publication date 3 Jan. 2002. Vasopressin acts on the kidney to increase water retention and so reduce urine output. For this reason, vasopressin is alternatively known as “antidiuretic hormone”. It also acts on the vasculature, where it produces a hypertensive effect. The cellular receptors that mediate these two actions have been characterised and shown to be different. The antidiuretic action is mediated by the type-2 vasopressin receptor, commonly called the V2 receptor. Agents that can interact with the V2 receptor and activate it in the same way as vasopressin are called V2 receptor agonists (or simply V2 agonists). Such agents will have an antidiuretic action. If these agents interact selectively with the V2 receptor and not the other vasopressin receptor subtypes, then they will not have the hypertensive effect of vasopressin. This would be an important safety consideration and make such agents attractive for the treatment of human disease conditions characterised by polyuria (which is herein taken to mean excessive urine production).
There remains a need for alternative V2 agonists. Such compounds may advantageously be easy-to-synthesize non-peptides.